tyranny

2. the condition or state of being dominated or controlled by something that makes unpleasant or harsh demands: 

• the tyranny of fashion drives many women to diet although they are not overweight.
  

... Collins Essential

noun: oppression, cruelty, dictatorship, authoritarianism, reign of terror, despotism, autocracy, absolutism, coercion, high-handedness, harsh discipline, unreasonableness, imperiousness, peremptoriness

... Collins Essential Thesaurus